The present invention relates generally to brake designs for rail cars, and more specifically to truck mounted brake systems.
Truck mounted brakes throughout the railroad industry include either a double actuator system as illustrated in U.S. Pat. No. 3,499,507 or a single actuator system as illustrated in U.S. Pat. Nos. 5,400,874 and 5,495,921. In all three of these systems, the actuator rods extend through holes in the bolster of the truck. The primary and secondary beams are unitary cast iron beams. The beams are U-shaped having a vertical base and two horizontal walls extending therefrom. The actuator or actuators are mounted to the vertical base and the actuator rods are mounted and extend through openings also in the vertical base. The brake heads are cast integral at each end of the beam.
Another example of a truck mounted brake having a single actuator is illustrated in U.S. Pat. Nos. 4,766,980 and 4,653,812. By moving the actuator rods outside of the center section, they pass under the bolster of the truck and no holes through the bolsters are required. The brake beams are shown as having a rolled steel center channel section with removable end sections having cast brake shoe heads and projecting guide end extensions bolted to the center section. The load on the beam is carried by the bolts which join the end sections to the center section. As with the previous unitary beams, the channeled portion is generally U-shaped having a vertical base wall with two opposed horizontal walls extending therefrom.
A unitary brake head and projecting guide end extensions secured to a bow type beam by fasteners is illustrated in U.S. Pat. Nos. 5,810,124 and 5,069,312. Again, the fasteners are load bearing and as described in the '124 Patent, rivets are used. Separate brake shoe heads and guide end extensions being secured by a common fastener is illustrated in U.S. Pat. No. 2,491,086. As in the '124 Patent, from the same assignee, rivets are used since they are a load bearing connection. Removable brake heads are also shown in U.S. Pat. Nos. 4,771,868 and 5,806,634.
There is a continuous drive to reduce the cost, size and weight of the truck mounted brake.
The present invention is a truck mounted rail brake including at least a primary beam having a center section and a pair of end sections with guide end extensions to be received in the slots of the truck. The center portion may include two opposed channel elements joined to each other and each having a horizontal base and two vertical walls. A brake actuator is connected to the primary beam and a brake head is removably joined to each end section of the beam. Preferably, the brake head is joined to the end section by a pin. In one embodiment, a tab is provided on the head and a portion of the tab is bent over the pin to retain it in the brake head and the end section. In a second embodiment, a second pin is removably joined to the brake head and extends above the first pin along an axis transverse to and intersecting an axis of the first pin to retain the first pin in the brake head and the end section. The first pin is dimensioned to allow the brake head to pivot about the first pin whose axis is transverse to the longitudinal axis of the beam.
With respect to the beam, the vertical walls of the opposed channeled elements may extend either from the base towards each other or away from each other. The channel elements are joined by a first weldment. The first weldments are hollow and the bases include openings to the hollow of the first weldments. The cross-section of the end portions of at least one of the channeled elements are smaller than the cross-section of a center portion of the at least one channeled element.
A second brake beam may be included also having a center section with a pair of end sections including guide end extensions. The second beam also includes at least one channel member having a horizontal base and two vertical walls.
Another truck mounted rail brake would include at least a primary beam including a center section, and at each end, an end section having a guide end extension to be received in the slots in a truck. A brake head has a slot in the back which receives the end sections and which allows removal of the brake head transverse the longitudinal axis of the beam. A first pin extends through the aligned aperture in a wall of the slot and in the end section and removably maintains the brake head on the end section. In one embodiment, a tab is provided on the brake head and a portion of the tab is bent over the pin to retain the pin in the brake head and the end section. In a second embodiment, an opening is provided in the brake head above the slot and has an axis transverse to and intersecting coaxial axis of the aligned apertures. A second pin extends through the opening above the first pin to retain the first pin in the apertures.
The brake beam further includes two transverse walls, one on each side of the brake head to limit the movement of the brake head along the longitudinal axis. The slot, first pin and separation of the transverse wall is already dimensioned to allow the brake head to pivot about the pin. The slot is formed by two flanges extending from the back of the brake head and vertically spaced sufficiently to receive the end section of the beam. A portion of the center section of the beam extends laterally below a portion of the end section. A third flange extends from the back of the beam and is vertically spaced from the other two flanges sufficiently to engage a portion of the center section of the beam below the end section as a stop.
Another truck mounted brake includes at least a primary beam including along a longitudinal axis, a center section and at each end, an end section having an end extension to be received in a slot in a truck. A brake head is removably mounted to the end extension by a first pin which is dimensioned to allow the head to pivot about the pin, whose axis is transverse to the longitudinal axis of the beam. As in the previous embodiments, the first pin is retained either by a tab on the brake head or a second pin which extends above the first pin along an axis transverse to and intersecting the axis of the first pin.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.